package com.wuys.frame.util;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * java几秒前/几分钟前/几小时前/几天前/几月前/几年前的工具类
 * <p>
 *
 * @author   WYS
 * @date	 2015年11月3日
 * @version  V1.0.0
 */
public class RelativeDateFormat {


	private static final long ONE_MINUTE = 60000L;

	private static final long ONE_HOUR = 3600000L;

	private static final long ONE_DAY = 86400000L;

	private static final long ONE_WEEK = 604800000L;


	private static final String ONE_SECOND_AGO = "秒前";

	private static final String ONE_MINUTE_AGO = "分钟前";

	private static final String ONE_HOUR_AGO = "小时前";

	private static final String ONE_DAY_AGO = "天前";

	private static final String ONE_MONTH_AGO = "月前";

	private static final String ONE_YEAR_AGO = "年前";


	public static void main( String[] args ) throws ParseException {

		SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:m:s");

		Date date = format.parse("2015-11-3 15:11:35");

		System.out.println(format(date));

	}


	public static String format( Date date ) {

		long delta = new Date().getTime() - date.getTime();

		if ( delta < 1L * ONE_MINUTE ) {

			long seconds = toSeconds(delta);

			return (seconds <= 0 ? 1 : seconds) + ONE_SECOND_AGO;

		}

		if ( delta < 45L * ONE_MINUTE ) {

			long minutes = toMinutes(delta);

			return (minutes <= 0 ? 1 : minutes) + ONE_MINUTE_AGO;

		}

		if ( delta < 24L * ONE_HOUR ) {

			long hours = toHours(delta);

			return (hours <= 0 ? 1 : hours) + ONE_HOUR_AGO;

		}

		if ( delta < 48L * ONE_HOUR ) {

			return "昨天";

		}

		if ( delta < 30L * ONE_DAY ) {

			long days = toDays(delta);

			return (days <= 0 ? 1 : days) + ONE_DAY_AGO;

		}

		if ( delta < 12L * 4L * ONE_WEEK ) {

			long months = toMonths(delta);

			return (months <= 0 ? 1 : months) + ONE_MONTH_AGO;

		} else {

			long years = toYears(delta);

			return (years <= 0 ? 1 : years) + ONE_YEAR_AGO;

		}

	}


	private static long toSeconds( long date ) {

		return date / 1000L;

	}


	private static long toMinutes( long date ) {

		return toSeconds(date) / 60L;

	}


	private static long toHours( long date ) {

		return toMinutes(date) / 60L;

	}


	private static long toDays( long date ) {

		return toHours(date) / 24L;

	}


	private static long toMonths( long date ) {

		return toDays(date) / 30L;

	}


	private static long toYears( long date ) {

		return toMonths(date) / 365L;

	}
}
